The Remote Systems Group has used Masterfl ex pumps for fl uid transfers since 1999. More recently,
when it came to transferring 76 pounds of mercury from a standard storage fl ask into containment
vessels, the Masterfl ex I/P® Precision Brushless Drive with Analog Remote proved to be advantageous
on many levels. Along with the Masterfl ex I/P Easy-Load® pump head and compatible Tygon® long-life
tubing, the pump system solved several of the groupís dilemmas at one time.

Mercury, a highly reactive and toxic
substance, can damage the central
nervous system, kidneys, lungs,
and brain when one is exposed
to high enough doses. Mercury poisoning
may trigger symptoms including swelling,
peripheral neuropathy, and skin-shedding.
Scientists in the Remote Systems Group of
the Oak Ridge National Laboratory (ORNL)
who have handled elemental mercury
transfers are well aware of its hazards. The
team initially conducted mercury transfer as
part of the Spallation Neutron Source (SNS)
project and later the MERcury Intense Target
(MERIT), a high-energy physics collaboration
for demonstrating a flowing mercury-jet target
in an intense magnetic field. More recently,
ORNL researchers investigated the structural
integrity of decades-old mercury storage
flasks, which required transferring mercury
into new flasks.

Far-Reaching Implications
ORNL is a US Department of Energy (DOE)
facility that delivers technical breakthroughs
in clean energy and global security. As the
largest DOE science and energy laboratory,
ORNL s research and development in
neutron science, materials science and
engineering, and nuclear science and
technology have far-reaching applications.
ORNL s examination of the properties of
materials at a subatomic level, using the
SNS, may ultimately lead to improved
medicines, metals, plastics, and ceramics.

Yet, mercury transfer can be a risky business.
The project s engineers and technicians put
on side-shield goggles, nitrile gloves, lab
coats, and safety shoes according to ORNL s
safety standards. With precautionary
respirator training and the use of snorkels and
fume hoods to mitigate vapours, scientists
are relatively well protected. However when
using centrifugal and/or vacuum pumps to
transfer the substance, the pump mechanics
became contaminated. The team needed a
better solution. "At the time, we investigated
¬blood pumps which are used in the
medical and food industry," explained Philip
Spampinato, an ORNL senior engineer.
"That search led us to peristaltic pumps,
which led us to the Masterflex® pump."

The Right Technology for the Task
The Remote Systems Group has used
Masterflex pumps for fluid transfers since
1999. More recently, when it came to
transferring 76 pounds of mercury from a
standard storage flask into containment
vessels, the Masterflex I/P® Precision
Brushless Drive with Analog Remote
proved to be advantageous on many levels.
Along with the Masterflex I/P Easy-Load®
pump head and compatible Tygon® long-life
tubing, the pump system solved several of
the group s dilemmas at one time.

"The quantity of mercury flow can be
controlled by varying the pump speed
and occlusion," said Spampinato."The
mechanical components of the pump do not
become contaminated. The mercury only
comes into contact with the tubing. This
decreases the risk of exposure to elemental
mercury and its vapours. We only need to
be concerned about safely discarding the
tubing when it becomes necessary to replace
it. Finally, because the tubing is clear, the
operator can visually observe the transfer.
This provides an added level of confidence
that the process is working well."

It also automates a process that might
have otherwise been handled manually,
a prospect that is both ineffective and
potentially hazardous.

"The Masterflex pump system is a
significant advantage compared to pouring
mercury out of a flask that weighs about
80 pounds," said Spampinato. "While the
viscosity of mercury is similar to water, its
density is 13.6 times that of water and it is
a nonwetting liquid. Therefore, controlled
pouring is virtually impossible."